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Around 50 years later, and even further south, the Vikings took over York, which had been developed as a city by the Romans and then the Anglo Saxons. Having mastered both agriculture and metalworking, the Vikings could lay claim to be the most “civilised” people in northern Europe. With boundless entrepreneurial energy, and the best technology they could lay their hands on, they invested heavily in their new asset to turn it into a world-class trading centre. They were, perhaps, too successful as pre-medieval city-builders, and they, too, were soon to be the subject of a take-over.
 
Both genetic studies and historic literature suggest the Vikings had a much greater influence on North Britain than the Romans or other invaders from the south. They were feared as warriors, but they were skirmishers and traders, rather than empire-builders. They would leave attempts at that last and dubious activity to their cousins, the Normans.